Find equations of the lines passing through the origin that are tangent to a circle with radius 2 and center at point (2,1). Please explain!

Marla bought a book for $12.95, a binder for $3.49, and a backpack for $44.99. the sales tax rate is 6%. find the amount of tax and the total she paid for these items

Janie has $3. she earns $1.20 for each chore she does and can do fractions of chores. she wants to earn enough money to buy a cd for $13.50. write an inequality to determine the number of chores, c, janie could do to have enough money to buy the cd.

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?